Integrated circuit comprising a current source of modulated intensity and corresponding generation method

Abstract

The integrated circuit comprises a current source configured to generate a control current whose intensity is modulated by an input signal. The current source includes a first stage configured to autonomously generate a constant component of the control current, and a second stage configured to autonomously generate a control current component that is modulated by the input signal.

1 . An integrated circuit comprising a current source configured to generate a control current whose intensity is modulated by an input signal, wherein the current source includes a first stage configured to autonomously generate a constant component of the control current and a second stage configured to autonomously generate a control current component that is modulated by the input signal. 
     
     
         2 . The integrated circuit of  claim 1 , wherein the current source includes a reference generator circuit configured to generate a reference current, the first stage includes a first current mirror assembly powered by the reference current, and the second stage includes a second current mirror assembly powered by the reference current. 
     
     
         3 . The integrated circuit of  claim 2 , wherein the second stage includes a converter circuit configured to generate a modulation current having an intensity that varies as a function of the input signal and to inject or extract the modulation current into or from the reference current powering the second current mirror assembly. 
     
     
         4 . The integrated circuit of  claim 1 , wherein the second stage is configured to generate the control current component that is modulated proportional to an average value of an amplitude of an AC signal as the input signal. 
     
     
         5 . The integrated circuit of  claim 1  further comprising a system controlled by a control loop, wherein the control loop comprises said current source, and the control current is configured for controlling an output signal of the system. 
     
     
         6 . The integrated circuit of  claim 5 , wherein the system includes a crystal oscillator configured to generate an AC output signal of the system, wherein the AC output signal of the system is the AC input signal of the control loop. 
     
     
         7 . A method comprising:
 generating a control current whose intensity is modulated by an input signal, wherein generating the control current includes a first autonomous generation of a constant component of the control current and a second autonomous generation of a control current component that is modulated by the input signal.   
     
     
         8 . The method of  claim 7 , wherein generating the control current includes generating a reference current powering said first autonomous generation and said second autonomous generation. 
     
     
         9 . The method of  claim 8 , wherein the second autonomous generation of the control current component that is modulated includes generating a modulation current whose intensity varies as a function of the input signal and injecting or extracting the modulation current into or from the reference current powering said second generation. 
     
     
         10 . The method of  claim 7 , wherein the control current component that is modulated is proportional to an average value of an amplitude of an AC input signal. 
     
     
         11 . The method of  claim 7  further comprising:
 controlling a system by a control loop, wherein the control loop comprises generating the control current; and 
 controlling an output signal of the system with the control current. 
 
     
     
         12 . The method of  claim 11  further comprising:
 generating an AC output signal of the system by a crystal oscillator, wherein the AC output signal of the system is the AC input signal of the control loop.